Kyo in his original body or in Kyoshiro's body? in any one of them he would cut kenshin to pieces before the latter can even feel it. Biakara might be faster than Kenshin and still he was so slow compared to Kyo in Kyoshiro's body even in an early stage of the manga.

Kyo wins and honestly Kenshin wont be able to withstand Suzako (The phoenix attack)